Starting next year, Bank of America will charge a small number of customers an annual fee, ranging from $29 to $99. The bank has characterized the fee as experimental. But card holders who have never carried a balance or paid late fees could be among those affected.

Citigroup, meanwhile, has started charging annual fees to card holders who don’t put more than a specific amount on their cards, typically $2,400 a year. Other banks are charging inactivity fees if customers don’t use their credit cards during a specific period of time. You heard that right: You could be spanked for staying out of debt.

These fees are the credit card industry’s response to credit card legislation that will, among other things, restrict credit card issuers’ ability to raise interest rates on existing balances. Credit card issuers are looking for ways to raise income before the new rules take effect in February. During the first quarter, 27% of credit card offers included annual fees, up from 18% a year earlier, according to Synovate Mail Monitor, a credit card direct-mail tracking service.

Curtis Arnold, founder of CardRatings.com, says he expected credit card issuers to raise annual fees after the legislation was enacted. What he didn’t expect, he says, « was that good customers were going to be hit. »

For now, Bank of America says the fees are being assessed on less than 1 percent of its credit card customers, but declined to give specifics.

There were about 80 million Bank of America credit cards in circulation last year, according to CreditCards.com; 1 percent of that is 800,000. Even half that figure provides a large enough sample size to make anyone conducting a scientific study envious.

« If (the test) proves successful, it could become the norm, » said Woolsey of CreditCards.com. « It’s somewhat up to consumer reaction. »